In:
Atmospheric Measurement Techniques, Copernicus GmbH, Vol. 12, No. 12 ( 2019-12-11), p. 6541-6556
Abstract:
Abstract. A method is assessed which expands aerosol vertical
profiles inferred from nadir-pointing lidars to cross-track locations next
to nadir columns. This is achieved via matching of passive radiances at
off-nadir locations with their counterparts that are collocated with lidar
data. This spectral radiance matching (SRM) method is tested using profiles
inferred from Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) lidar observations and collocated Moderate Resolution Imaging
Spectroradiometer (MODIS) passive
imagery for the periods 10–25 April and 14–29 September 2015. CALIPSO
profiles are expanded out to 100 km on both sides of the daytime
ground track. Reliability of constructed profiles that are removed from the
ground track by number of kilometers are tested by requiring the algorithm to reconstruct
profiles using only profiles that are removed from it along track by more
than the number of kilometers. When sufficient numbers of pixels and columns are available, the SRM
method can correctly match ∼75 % and ∼68 %
of aerosol vertical structure at distances of 30 and 100 km from the
ground track, respectively. The construction algorithm is applied to the
eastern coast of Asia during spring 2015. Vertical distributions of different
aerosol subtypes indicate that the region was dominated by dust and polluted
dust transported from the continent. It is shown that atmospheric profiles
and aerosol optical depth (AOD) inferred from ground-based measurements
agree with those constructed by the SRM method. For profiles, the relative
errors between those measured by ground-based lidar and those constructed in
the surrounding area are similar to the relative errors between the ground-based
station and CALIPSO overpass at the closest distance. For AOD, the measurements
from the ground-based network agree with those inferred from constructed aerosol
structure better than direct observations from CALIPSO and close to those
inferred from MODIS radiances.
Type of Medium:
Online Resource
ISSN:
1867-8548
DOI:
10.5194/amt-12-6541-2019
Language:
English
Publisher:
Copernicus GmbH
Publication Date:
2019
detail.hit.zdb_id:
2505596-3
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